Electronic components such as, for example, a Central Processing Unit (CPU) used in a high-performance information processing apparatus, which is called a data center server or a supercomputer, generate a large amount of heat during the operation thereof. An allowable upper-limit temperature is set for these electronic components, and, when these electronic components exceed the allowable upper-limit temperature, a deterioration in the processing capability of the information processing apparatus, or a malfunction or failure of the information processing apparatus may be caused. Therefore, it is important to cool the electronic components such that the temperature of the electronic components does not exceed the allowable upper-limit temperature.
Cooling devices for cooling electronic components include an air cooling type cooling device and a water cooling type cooling device. Since large-scale data centers and supercomputers require a reduction in operation costs, the water cooling type cooling device, which may reduce the operation costs compared to the air cooling type cooling device, is often adopted.
The water cooling type cooling device includes a cooling plate, which is attached to a component that generates a large amount of heat (hereinafter referred to as a “heat generating component”), a heat dissipation unit, which is disposed at a place distant from the cooling plate, and a pump, which circulates cooling water between the cooling plate and the heat dissipation unit.
The cooling plate is formed of a metal having high thermal conductivity, and a flow path, through which the cooling water flows, is formed inside the cooling plate. In addition, the heat dissipation unit is provided with a heat dissipation device such as, for example, a radiator.
The heat generated from the heat generating component is transported to the heat dissipation unit by the cooling water passing through the cooling plate, and dissipated from the heat dissipation unit to the atmosphere. In addition, the cooling water, the temperature of which has been lowered as the heat dissipation unit dissipates the heat, is again sent to the cooling plate by the pump.
In addition, herein, water or other coolant, which is used to transport the heat from the cooling plate to the heat dissipation unit, is called cooling water.
In the related art, there has been proposed a technique of improving heat dissipation efficiency by forming an inclined surface on each of a heat generating component and a cooling member, which cools the heat generating component, so that heat is transferred from the heat generating component to the cooling member via the inclined surfaces.
In the information processing apparatus, heat is generated not only in a semiconductor component such as, for example, a CPU, but also in a power supply unit. In the related art, a cooling plate is attached to a semiconductor component such as, for example, the CPU, which generates a large amount of heat, and a power supply unit and other components, which generate a small amount of heat, are air-cooled using a relatively small fan.
However, with higher performance, the power consumption of servers or supercomputers is increasing, and the amount of heat generated by power supply units or the like is also increasing. Therefore, cooling using a water cooling method has been studied with respect to power supply units or the like as well.
Generally, a power supply unit is provided with relatively large electronic components such as, for example, a transformer, and these components generate a large amount of heat. However, in the case of an electronic component (heat generating component) such as, for example, a transformer, it is impossible to cool the entire electronic component simply by bringing a portion of the electronic component into contact with the cooling plate.
The followings are reference documents.    [Document 1] Japanese Patent Laid-Open Publication Nos. 01-132146,    [Document 2] Japanese Patent Laid-Open Publication 2008-153464, and    [Document 3] Japanese Patent Laid-Open Publication 06-132686.